Skin fungus threatens fire salamander
The fire salamander crawls leisurely through the moss. It is definitely not one of the fastest amphibians and its black and yellow pattern immediately catches the eye. But it has nothing to fear here: The salamander lives in an enclosure at Nuremberg Zoo. Some time ago, however, it was still in great danger. It was infected with the skin fungus Bsal (Batrachochytrium salamandrivorans), also known as the salamander fungus or salamander plague - which is usually fatal.
However, the fire salamander and four of its conspecifics were lucky. Conservationists found them in the Steigerwald forest in the north of Bavaria and brought them to the Nuremberg Zoo. There, vet Hermann Will was able to cure them. The infected amphibians spent two weeks in a heating cabinet - at a temperature of 25 degrees, which kills the fungus and which the fire salamanders can just about withstand, as Will explains. "They survived the treatment well."
Since then, the fire salamanders have been living in a small outdoor terrarium at Nuremberg Zoo and will probably stay there. It is not possible to release them back into the Steigerwald, says Will. The recovered animals are not immune to a new infection. The zoo would therefore like to use this to establish a conservation breeding program for the fire salamander. This is because it is considered endangered in Bavaria and is on the Red List of Threatened Species for Germany as a whole.
Children know the fire salamander (Salamandra salamandra) as the cartoon character "Lurchi", who advertises a shoe brand. With its eye-catching pattern - yellow spots on a black lacquer background - it is not only particularly pretty to look at, but is also the largest tailed amphibian in Germany, measuring up to 20 centimetres in length. According to the German Society for Herpetology and Terrarium Science (DGHT), this makes it probably the best-known amphibian species in this country.
Several dangers
However, most people have probably never seen it in the wild. The fire salamander is mainly nocturnal and feels most at home in semi-natural mixed deciduous forests in the low mountain ranges with small streams and ponds where it can lay its larvae. However, this habitat is disappearing.
Climate change is also causing problems for fire salamanders. "The drought is causing them problems," explains Malvina Hoppe from the LBV nature conservation association. "If small streams and ponds dry up before the larvae have developed, it becomes critical." Then there is the deadly skin fungus Bsal. In the Ruhr region, this has led to a mass extinction, says biogeography professor Stefan Lötters from the University of Trier. He has been researching the salamander plague for a long time, but still sees many unanswered questions.
The skin fungus, which originated in Asia, probably came to Europe via the animal trade, says Lötters. It was first detected in the Netherlands in 2010, and later in Germany, Belgium and Spain. In Germany, the fungus occurs in the Ruhr region, the Eifel, the Steigerwald and the Allgäu. In the Allgäu, where there are no fire salamanders, it attacks newts, but they do not die from it.
Much research still needed
From Lötter's point of view, it is still a mystery why there has not yet been a mass extinction in the Steigerwald as in the Ruhr area. "My guess is that there is a different variant of the fungus there that is not as aggressive. But we have no data on this." It is also still unclear how long Bsal has actually been present in the affected regions. "We have evidence that it appeared near Aachen as early as 2004. But it is no longer found there today." Lötters concludes: "Somehow, the fungus seems to be able to disappear again." But how is still unknown.
According to Lötters, there is no danger of the fire salamander becoming extinct in Germany any time soon. "But we believe we are seeing a spread of Bsal." He therefore believes it makes sense to help conserve the species with captive populations. "Until we know more about the fungus, how we can combat it or it dies out," says Lötters.
Several stations for breeding
There is currently only room for a few fire salamanders at Nuremberg Zoo. However, a large outdoor enclosure is being planned. The zoo in Wuppertal said it had already started a pilot project with the university and the Lower Nature Conservation Authority in spring, for which fire salamanders and their larvae are taken from the wild, tested for Bsal and then transferred to the breeding station after a quarantine period.
Other zoos and private keepers in Germany are also participating in a conservation breeding programme coordinated by the Citizen Conservation organization. This was founded by the DGHT, the Association of Zoological Gardens and the Frogs & Friends initiative. More than 150 fire salamanders in 16 enclosures are currently involved, says project manager Johannes Penner. He believes it is important to act proactively. Because the actual threat posed by Bsal is not known. The last classification of the fire salamander on the Red List dates back to 2020, but the skin fungus was not taken into account.
However, there is also good news: "The fungus itself spreads very slowly," says Lötters. "So there must be vectors." For example, forest animals or people who carry the spores from one place to another. At least the latter can be targeted to prevent this: the Bavarian nature conservation association LBV calls on all people to always stay on the paths in Bsal hotspots and to disinfect shoes, car and bicycle tires to prevent the spores from spreading.
The fire salamander's natural habitat, primarily semi-natural mixed deciduous forests, is under threat due to climate change and habitat loss. These dangers, coupled with the deadly skin fungus Bsal, make nature conservation efforts crucial for the survival of this species. The fire salamander is currently being used in several conservation breeding programs across Germany, including at the Nuremberg Zoo and a pilot project in Wuppertal, to maintain population numbers and protect the species from potential extinction.
Source: www.dpa.com
